Insomnia - API Client That Doesn't Suck

Look, another API client review. But here's the thing - I've been debugging APIs at 3AM long enough to know which tools actually work when everything's on fire. Insomnia isn't perfect, but it gets the job done without the bullshit that makes other clients unusable.

The Kong Acquisition That Didn't Ruin Everything

Gregory Schier built Insomnia because existing tools were slow, bloated, or paywalled to death. Kong acquired it in April 2019, and surprisingly, they didn't destroy it. The current stable release is version 11.5.0 as of August 2025, and it's still actively maintained.

Unlike Postman's RAM-eating monster approach, Insomnia keeps things clean. It's built on Electron (yeah, I know), but they've kept the bloat under control. Memory usage stays reasonable - around 150-200MB vs Postman's 800MB+ appetite.

GraphQL Support That Actually Works

This is where Insomnia shines. GraphQL schema introspection works like magic - point it at an endpoint and it discovers your entire schema without breaking. The query builder has autocomplete that actually understands your types, and mutations don't require sacrificing a goat to the API gods.

I've tested it with Shopify's GraphQL API (their schema is massive) and it handles it without choking. Loading takes a while with big schemas, but once it's cached, querying is smooth. The GraphQL Foundation recommends introspection as a key feature, and Insomnia implements it properly.

Git Sync Without the Headaches

Native Git integration means your collections live in version control where they belong. No more "can you send me the latest collection?" conversations. Branching works, merging works, and conflicts get resolved without losing work.

The sync process connects to GitHub, GitLab, or any Git host. When someone updates a collection, you pull the changes like any other code. It's not revolutionary, but it works consistently. Unlike Postman's cloud sync issues, Git-based workflows are reliable.

Open Source Reality Check

Being open-source means a few things:

• Data ownership: Collections are stored locally as files you can backup, version, and migrate
• Plugin ecosystem: Community extensions, though smaller than Postman's
• Transparency: You can see exactly what it's doing with your API credentials
• No vendor lock-in: Export your data anytime, or fork the project if Kong screws it up

The plugin ecosystem isn't huge, but the core functionality is solid enough that you might not need much extra.

Where It Falls Short

Let's be honest about the problems:

Import/export pain: Migrating from Postman works about 70% of the time. Complex auth setups usually break and need manual reconstruction.

Team collaboration: Free tier is limited. The paid features for teams are reasonable but still cost money.

Plugin ecosystem: Smaller than Postman's extensive marketplace. Most plugins work, but selection is limited.

Enterprise features: Kong pushes their enterprise stuff, which can feel heavy for simple API testing needs.

When Insomnia Makes Sense

Use it if: You do GraphQL work, want Git-based workflows, prefer open-source tools, or are already in Kong's ecosystem.

Skip it if: You need extensive team collaboration features, have complex Postman workflows that can't migrate, or want the biggest plugin selection.

The tool works well for individual developers and small teams who value clean interfaces and don't want to pay enterprise prices for basic API testing.

Installation That Actually Works

Download from the official site - they have packages for Windows, Mac, and Linux. The installers work without weird dependencies or configuration hell.

On Ubuntu: sudo snap install insomnia
On Mac: brew install --cask insomnia
On Windows: Download the installer and click through it like a human.

No account required to start testing APIs, which puts it ahead of tools that lock basic functionality behind registration walls. The download process is straightforward without dark patterns.

First API Request in Under 5 Minutes

Create a new request, set the method and URL, add headers if needed, send it. The response viewer handles JSON, XML, and plain text without plugins. Authentication helpers cover Basic, Bearer, OAuth, and the usual suspects.

For GraphQL, create a new GraphQL request type, point it at your endpoint, and let schema introspection do its thing. Query building becomes point-and-click instead of memorizing field names. Compare this to Postman's clunky GraphQL support where introspection barely works.

Environment and Variable Management

Environment variables work like you'd expect - define them once, use them everywhere. Base URLs, API keys, and tokens stay in environment files instead of hardcoded in requests.

The template system uses Nunjucks syntax ({{ variable_name }}) for dynamic values. It's not exciting, but it works consistently across request URLs, headers, and bodies. This is more reliable than Postman's variable scoping issues that plague complex collections.

Collections and Organization

Projects contain collections of requests organized in folders. The folder structure makes sense - group related endpoints together, inherit authentication from parent folders, and keep things findable.

Git sync turns collections into version-controlled files. Connect to a repo, and changes sync across team members automatically. No more collection corruption from multiple people editing simultaneously.

Authentication That Doesn't Break

OAuth 2.0 flows work through the built-in browser without external redirects. PKCE support handles modern security requirements. JWT tokens get parsed and displayed so you can see expiration times and claims.

For APIs with custom auth schemes, the pre-request script system lets you build tokens programmatically. Not as flexible as Postman's scripting, but handles most real-world scenarios without the Newman CLI complexity.

Plugin Ecosystem Reality

The plugin system exists, but selection is limited. Most useful plugins:

• Faker: Generate test data
• AWS signature: Sign AWS API requests
• Custom themes: Make it look different
• Export formats: Additional import/export options

Don't expect Postman's massive plugin marketplace. The core feature set covers most needs, but specialized use cases might require custom solutions.

Performance and Stability

Memory usage stays reasonable during normal use. Large response bodies (multi-MB JSON) can slow things down, but it handles typical API responses fine.

Startup time is decent for an Electron app - a few seconds on modern hardware. Response time display includes network timing breakdowns to help identify bottlenecks.

The app crashes occasionally (it's Electron), but auto-recovery usually works. Keep backups of important collections because shit happens.

Data Storage and Backup

Collections are stored as local files you can backup and version. The storage format is human-readable JSON, so migration tools can parse it if needed.

Cloud sync is available in paid plans, but local storage works fine for individual use. Git sync provides team collaboration without vendor lock-in.

Export supports multiple formats including Postman collections, HAR files, and OpenAPI specs. Import works with most common formats, though complex setups usually need manual fixing. The data portability is better than vendor-locked alternatives.